The San Diego International Fringe Festival, whose fifth edition is now in full (and often freaky) flower here and in Tijuana, is a definition-defying mix of theater, dance, music and multiple other modes of expression. (Check out our full preview here.)

Some of its 80-odd shows, of course, take on familiar forms: Short plays, comic and/or confessional monologues, choreographic showcases.

And then something comes along that will make you say: “Only at Fringe.” (And thank the weird-art gods — and festival organizers — for that.)

The piece, presented by Bodhi Tree Concerts — a major fest presence over the past few years — was created in 1969 by the late Sir Peter Maxwell Davies, a composer who was an iconoclast in the extreme.

Davies wrote “8 Songs” as an ode to the “mad” King George III, who ruled England during the American Revolution and whose increasingly erratic behavior may have been caused by the blood disease porphyria.

It’s a trippy chamber-music piece that at times is a cacophony of keening strings, pounding percussion and jittery trills of flute and piccolo. (It’s inspired both by George’s own words and songs from a music box with which he apparently tried to teach birds to sing.)

But at the center of the work is the careening figure of the “king” himself, played in the Bodhi Tree show by the impressive Walter DuMelle in full Trump-ian glory — long red tie, fussy hair, phone at the ready for a tweetstorm.

If you go to the show (staged-directed by Kim Strassburger, with music direction by Brendan Nguyen), you can’t miss him: He’s the guy stomping down the length of the runway-lake tabletop at which you and most other attendees are seated.

The show is full of strange and funny vocalizations — whoops and shouts and octave-leaping bits of sung text.

What’s most fun, though, is that production-team member Jason Ponce has created a kind of in-house live-tweeting system (dubbed “Trash Talk Theater”) that allows everyone else at the show to log in on mobile devices and start tapping out timely/snarky observations on the happenings.

Those messages are then displayed on TV screens arrayed around the venue, the Bivouac Ballroom in downtown’s U.S. Grant Hotel

It can create a bit of disconnect for the audience to be both watching the screens and DuMelle’s performance — and at times to be lost in fits of laughter at a particularly witty tweet, while the music (played with great skill by a live ensemble) has entered a brooding, somber passage.

But it’s also a perfect way to adapt “8 Kings” for a tweet-mad leader who thrives on attention; some authentic Trump tweets even pop up on the screen occasionally, further mixing the worlds of performance and politics.

In all, it’s a singular and memorable show full of both fun and frights, with music that fits the mood perfectly but is anything but catchy or comforting.

As one attendee tweeted in midperformance on Saturday night: “This is what my hangover sounds like.”

“8 Songs for a Mad King,” Bodhi Tree Concerts

Rob Elk of the solo show "We've Seen Enough." (Courtesy San Diego International Fringe Festival)

A couple of other quick hits from the first weekend of Fringe:

“We’ve Seen Enough” is writer-actor-songwriter Rob Elk’s look back at his show-biz career, from Iowa boyhood (big break: playing Abe Lincoln in a third-grade pageant) to forming the acts Modern Entertainment and then Mr. Elk and Mr. Seal, a duo that earned some national attention.

Locals might know Elk best as a longtime star of “Triple Espresso,” the record-setting comedy that ran for more than a decade at downtown’s Horton Grand Theatre.

But Elk is apparently better-known elsewhere for “The Thorazine Shuffle,” a deadpan ditty inspired by his experiences working in a mental hospital. (He tells a story during the solo show of how students at a Texas Tech performance knew every word of the tune.)

“We’ve Seen Enough” is a loose-limbed work informed by Elk’s self-deprecating humor; it feels as if it’s very much a work in progress, and leaves a sense that Elk probably has more and better stories he could weave in here. (The piece also seems oddly fixated on “Of Mice and Men,” the Steinbeck story that was a major influence on Elk when he saw it years ago at Minneapolis’ Guthrie Theater.)

“We’ve Seen Enough,” Rob Elk / BOP Productions

10:30 p.m. June 28; 7:30 p.m. June 30; 11:30 a.m. July 2. The Geoffrey Off Broadway, 923 First Ave., downtown.

The short play “The Fault of Falling” places us in a college dorm room where a story of love, guilt and lingering family drama (and trauma) unspools.

Lucy (Maybelle Covington, who wrote the piece) and Charlie (Mary Janus) have just officially become a couple as the story begins, while mutual friend Ben (Mitchell Evenson), who admits he once had eyes for the intensively alive Charlie himself, offers counsel and support.

But there are signs of trouble from the start. Charlie is reluctant to share the couple’s new status on social media, despite prodding from Lucy, the more earnest, responsible one of the pair. Charlie’s drinking also looms as a major issue after her intolerant family learns of her same-sex relationship.

There’s plenty of tension built into the piece, which is well-acted by the trio with a mix of narration and dialogue scenes. The struggles the characters face also feel authentic, although the play ultimately gets a bit stuck on the same minor-chord emotional note, and doesn’t leave us with much of a sense of resolution. (Of course, this might be envisioned as just one act of a longer piece.)

Covington does show a sympathetic eye for characters and a good touch for dialogue, boding well for noteworthy future work from this young writer.

“The Fault of Falling”

A quick reminder that today (Sunday, June 25) is Family Fringe, with a range of free events from noon to 6 p.m. at the City Heights Performance Annex, 3795 Fairmount Ave. in City Heights. For more info on that and all Fringe happenings, go to sdfringe.org. (Most Fringe shows are $10, although some are free; you’ll also need to buy a $5 Fringe tag, a one-time purchase good for the festival’s full 10-day run.)

In its first weekend, the festival overall seemed to be running in its usual smooth manner under executive producer/director Kevin Charles Patterson, managing director Candice Caufield, festival coordinator Todd Blakesley and their team. Shows at Balboa Park's Centro Cultural de la Raza on Saturday had to be canceled due to a memorial service there, but at least one of the acts — New Zealand’s “Allergic to Love: Curse of the ‘80s” — made it downtown for a modified performance at Club Fringe.

Speaking of which: That space, upstairs from Fringe headquarters on First Avenue just south of Broadway, continues to be a good place to chill between shows.